1. Field of the Invention
The present invention relates to a set-trigger mechanism applied to a gun such as a rifle, and specially to a releasing device for safely and securely releasing a trigger locked by the set-trigger mechanism.
2. Description of the Prior Art
Generally in firing with live bullets, it is not easy to obtain a best timing for discharging, since the sighting of a target by a gun being held by a shooter is not easily stabilized due to a balance of the gun itself, variation of the shooting condition such as a wind and so on, and in order to solve this problem, a so-called set-trigger mechanism has been developed so far, thereby to enable a firing of a gun even with a very subtle feathery touch to the trigger.
FIGS. 5 and 6 each shows a conventionally adopted set-trigger mechanism, and here a mechanism of the trigger itself is first explained as follows.
In these figures, reference numeral 1 denotes a receiver where the loading of a bullet into a barrel cartridge chamber (not shown) and removal of a bullet or an empty cartridge case therefrom are conducted. Reference numeral 2 denotes a bolt which is assembled together with a bolt handle 3 and a bolt shroud 4, and is rotated and reciprocated within the receiver 1 in accordance with an operation of the bolt handle 3 so that a bullet is loaded into the barrel cartridge chamber and set in a fire-enabling condition.
Reference numeral 5 denotes a firing pin shirr having at an opposite end thereof a firing pin which is protruding from a far end of the bolt 2. This firing pin shirr 5 is repulsively urged toward a nuzzle side of the gun (left side of the figure) by a spring (not shown) when it is set in a fire-enabling state, and a protruding portion 6a of a shirr 6 is engaged with a slanting portion 5a formed on the firing pin shirr 5.
The shirr 6 is rotatably supported by a shaft 6b formed at the left side thereof, and is also formed with another protruding portion 6c at its lower side. This protruding portion 6c loosely enters into a dented portion 7a of a trigger shirr 7 so as to hamper the protruding portion 6a from shifting its position downwardly, and thus hampering the firing pin shirr 5 from moving toward left side of the figure. The trigger shirr 7 is rotatable on an axis 8.
Reference numeral 9 denotes a trigger which is also rotatable on the axis 8, and when this trigger is pulled, it is rotated in a counterclockwise direction, so that a head portion 9a thereof pushes the upper portion of the trigger shirr 7 toward left side of the figure, disengaging the dented portion 7a from the protruding portion 6c to permit the shirr 6 to rotate in a clockwise direction, and then the slanting portion 5a goes over the protruding portion 6a and the firing pin shirr 5 instantly moves toward left to discharge a bullet.
A bullet is discharged from a gun by all these above movements. However, the trigger 9 should be pulled by a substantially large force in this case, and therefore it is not easy to get the best timing for discharging as mentioned before. With this background, a set-trigger mechanism has been developed, the mechanism of which is now explained hereinafter.
In FIGS. 5 and 6, reference numeral 10 denotes a roller arm rotatable on an axis 10a and having a roller 11 at an end portion thereof, and this roller arm 10 is repulsively urged in a counterclockwise direction by a spring 12. On the other hand, the trigger 9 is formed with a projection 9b having a sharpened point at its top end. When the trigger 9 is rotated in the opposite direction to that for discharging a bullet, that is, rotated in a clockwise direction, a set adjustment screw 13 is adjusted to lock the sharpened point of the projection 9b in an upper position than a line connecting the respective center points of the roller 11 and the axis 8, and by this adjustment, the trigger is locked by the set-trigger mechanism.
By lightly pulling the thus locked trigger 9 as shown in FIG. 6, the following actions are instantly done to discharge a loaded bullet. First, the projection 9b abruptly slides downward along the outer periphery of the roller 11 due to the repulsively urged force of the spring 12, the trigger 9 is thereby rotated in a counterclockwise direction, the head portion 9a thereof hits the trigger shirr 7 in the left ward direction, and then the dented portion 7a and the protruding portion 6c are disengaged from each other so as to discharge. In this case, since the projection 9b is formed with a sharpened point and is situated on the outer periphery of the roller 11, a conception that we conventionally had "to draw a trigger" is changed to "to touch a trigger", and thereby to greatly contribute to an improvement of a shooting technique.
However, since the above set-trigger mechanism is, as a matter of fact, performed in a state that a bullet is loaded and is enabled to discharge, once the trigger is locked by the set-trigger mechanism, the bullet is possibly discharged even by a very light feather-like impact. For example, if the bolt handle 3 is abruptly closed and operated, the trigger can easily be brought into a fire-enabling state, and therefore, once the trigger is locked, it should be treated with a meticulous attention.
In the above case, if the bullet is not discharged and still remains in the loaded state, the locked trigger should be released. However, if the releasing operation is not conducted with care, a sudden discharge of the bullet would accidentally occur, and therefore, in order to avoid this accidental phenomenon, the locked trigger should be firmly pressed first and put back up to the released position before moving the nuzzle of the gun away from the target, which requires a meticulous attention of the users.